Nasopharyngeal carcinoma (NPC) is defined as a malignant neoplasm that has its origin from the surface epithelium of the nasopharynx. This cancer has attracted world-wide interest because of the evidence which suggests that multiple factor including viral, genetic and environmental interact in the ethiology of this interesting disease. Because of the great interest in this cancer, three international symposia have previously been held, the last in 1980, covering various aspects of NPC from basic research to patient management. This has at least been partially responsible for the great strides that have been made in understanding this disease and in the application of new and useful information obtained in the laboratory to the clinics. The major objectives of the Fourth International Symposium on NPC to be held in Kuala Lumpur, Malaysia in September 1982 are: (1) to present and review new findings covering various aspects of NPC obtained since the last Symposium in 1980; (2) to initiate and formulate new plans for international collaborative research projects; (3) to stimulate more rapid application of laboratory findings to the clinics and to develop new approaches to therapy in high and low incidence areas; (4) to attempt to define new clinical and environmental findings which require further investigation in specific populations; and (5) to establish an active exchange of materials and data among scientists throughout the world.